I have some objects on the screen and would like to rotate only one of them. I tried using the glRotatef(...) function but turns out glRotatef(...) rotates all my objects (r
You need the rotation to be in effect only when the geometry you're interested in is being drawn.
... draw stuff ...
glPushMatrix();
glRotatef(angle, 0, 1, 0);
... draw rotated stuff ...
glPopMatrix();
... draw more stuff ...
Tutorial #4 from NeHe shows how to do that precisely.
Also, you might want to take a look at this:
OpenGL Rotation